Intended for connection to a polarity
reversal circuit of a Remote Station
receiving unit having compatible ratings.
The shunt connection is recognized only as a
supplementary signaling unit as part of a local
control unit and is not recognized as an auxiliary
control unit connection per NFPA 72.
NAC circuit 1 used as an example.
Any NAC circuit can be used.
non-supervised,
non-power-limited
city box
orange
yellow
red
brown
Figure 4.47 City Box Connection